The invention relates to a motor/generator which operates on the reluctance principle, with a flywheel mass rotor. A typical motor/generator is disclosed in German Patend DE-Os No. 29 17 139.
In this motor/generator, which is provided in connection with the internal combustion engine of a motor vehicle, the flywheel mass can be engaged by or disengaged from the crankshaft. In addition, the flywheel mass also forms the windingless rotor of the motor/generator which operates on the reluctance principle. The stator, which is not described in detail, is secured on the internal combustion engine or on the gearcase. The flywheel mass, which can be disengaged from the crankshaft by an additional clutch, is rotatable relative to the crankshaft when it is disengaged.
During brief stoppages, such as stopping for traffic lights, the flywheel mass is disengaged from the internal combustion engine so that it can continue to rotate even with the engine turned off. During subsequent restarting, the flywheel mass is re-engaged for starting the engine. In addition, during brief stoppages of the motor vehicle the flywheel mass is maintained by the motor/generator at a sufficient number of revolutions per minute to ensure starting of the engine when the flywheel is re-engaged by the engine. When the engine is in operation the motor/generator is switched to generator operation and electric power is provided to the vehicle battery.